$$4\,L$$ of $$0.02\,M$$ aqueous solution of $$NaCl$$ was diluted by adding one litre of water. The molality of the resultant solution is _____________.
A.
0.004$$\,m$$
B.
0.008$$\,m$$
C.
0.012$$\,m$$
D.
0.016$$\,m$$
Answer :
0.016$$\,m$$
Solution :
$$\eqalign{
& {M_1}{V_1} = {M_2}{V_2};0.02\,M \times 4\,L = {M_2} \times 5\,L \cr
& {M_2} = \frac{{0.02 \times 4}}{5} = 0.016\,M \cr} $$
Here, molality will be equal to molarity as for $$NaCl,$$ molecular weight is equal to its equivalent weight.
Releted MCQ Question on Physical Chemistry >> Solutions
Releted Question 1
An azeotropic solution of two liquids has boiling point lower than either of them when it